What is the potential of a 331 and be emission legal? Let see those combo's!!

runningmole said:
Greg, I'm switching from a 347 to 331. I already talked to Ed Curtis, and he said no problem on getting me a cam (I want to pass smog as well) I'm going to toss a Vortech on it too. If you go N/A, I don't see why you couldn't make at least 350rwhp w/ say 10.5 compression, AFR 185s, RPM Intake, FTI cam, full exhaust and all that stuff. You'll at least make a lot more torque.

Matt

I was just wondering why would you go from a 347 to 331? I would think the 347 would be better.
 
  • Sponsors (?)


Well I don't have a 331 but this still my help out. Its a 347. And it did pass emissions (here in Ca.), not even close to failure! heres the mods:
CHP 347, AFR 185's,10.5 to1 comp. , Cam with 523/541 212/222, Cobra intake, 30lb injectors, 255lph fuel pump, Areo fuel reg., motorsport short headers, BBK 70mm TB, 75mm MAF, Cold Air intake, MSD 6A, Flowmasters w/stock cats. etc. I never had it dynoed so I dont know how much Hp it was making but I'm sure it was over 300rwhp. I've now added a RPMII intake with Comp Cam and ditched the cats. This motor is totally street worthy and a blast to drive.
 
DavidF said:
Well I don't have a 331 but this still my help out. Its a 347. And it did pass emissions (here in Ca.), not even close to failure! heres the mods:
CHP 347, AFR 185's,10.5 to1 comp. , Cam with 523/541 212/222, Cobra intake, 30lb injectors, 255lph fuel pump, Areo fuel reg., motorsport short headers, BBK 70mm TB, 75mm MAF, Cold Air intake, MSD 6A, Flowmasters w/stock cats. etc. I never had it dynoed so I dont know how much Hp it was making but I'm sure it was over 300rwhp. I've now added a RPMII intake with Comp Cam and ditched the cats. This motor is totally street worthy and a blast to drive.

David...thanks for your contribution...your engine combo seems sweet. It would be helpful if you knew how much HP your're making...I already have accomplished 300RWHP from a 302 and just really want to know how much I can get out of a 331...

-Greg
 
The cam is a Comp Cam XE282HR with Duration at .050 = 232/240 and lift =.565/.574 with 112 degree lobe sep. Now I believe theres even more hp available with a little more lift, as the AFR 185's flow better at .600 lift.
 
I am in the last stages of my 347 buildup and I will be dissapointed if I dont make 345-375 HP. Ed is grinding my cam and will be assembling my 185's over the next couple weeks, and it is going to have to pass the sniffer test also. I cant wait till the weather brakes and I can drop this mutha in!
 
Highbredcloud said:
I was just expcting somwhere between 350RWHP and 380RWHP with a propperly built 331 such as AFR 185, RPM II intake and a custom cam along with the rest of the bolt-ons...but if it only will give about 30RWHP over a 302/306 that it's not really worth the stroker than...right? Someone's got to have a 331 NA on here that can shine some light.

Your pretty much have it exactly right, with that combo (similar to mine) u should hit those #s. I did alot of research and came up with similar numbers b4 choosing a 331 or 347. Most said that between a 347 and 331 with exact combos, maybe only a 15-20 HP difference. i dont think its as little as 30 between a 302. it will be significantly higher, as well as TORQUE.
 
Well mines not NA but I'll jump in. 390rwhp 400rwt 11.62@115mph in a car that weighs 3560- 3770 with me in it. GT40 intake,box stock Edelbrock 5.0s, 8-1 compression, 6psi of boost. Totally streetable, drive it anywhere. The whole buildup is on my site. Mike
 
i currently run dart block 331 ,edel performer rpm heads and intake, comp cam,s-trim,42lb. injectors,aeromotive comp. fuel kit,8:1,shorty headers, made 439rwhp at "crazy horse "with old fuel system(ran out of fuel at 4k rpm). very streetable !!! Should really come alive with the new fuel system!!
 
R6bullit alot of people use the 331 because if you run a 347 and god forbid if you bust a ring or a piston and scars up the cylinder wall, you are done you will need a new block, you can't bore it out any more, however you could sleeve it "cringe" that's scary
 
QWIKSVO said:
R6bullit alot of people use the 331 because if you run a 347 and god forbid if you bust a ring or a piston and scars up the cylinder wall, you are done you will need a new block, you can't bore it out any more, however you could sleeve it "cringe" that's scary

UUUHH..... The piston bore on a 331 and 347 are the same so I dont get what your trying to say?
 
I am also looking into a 331 anybody out there know some good kits that arent going to rape my bank account, but at the same time give me the streetable power i want, 350-400rwhp.